Ensure you have Nemesis or FNIS installed to handle the custom animations required for the physics to function correctly.
Install XP32 Maximum Skeleton Extended (XPMSSE) . This provides the necessary "bones" for the physics to attach to.
You generally need both CBPC (for collision-based "jiggle") and FSMP (Faster HDT-SMP) for more complex, fluid movement.
3BBB is not a standalone mod; it is an enhancement for the (Caliente's Beautiful Bodies Enhancer) base body that adds advanced physics to the breast, belly, and butt (hence the "3B" naming).
Once installed, the physics won't appear until you "build" the meshes in . Skyrim mods tutorial - how to use 3BBB
To use (often referred to as 3BA or "3 Breast Bone Body") in Skyrim , you must first install its foundational requirements— XP32 Maximum Skeleton Extended (XPMSSE) and a physics engine like FSMP (Faster HDT-SMP) —then use BodySlide Outfit Studio to build the body and outfit meshes that support the additional physics bones. The Core Setup: What You Need First